Network management is important to businesses, government agencies, schools, banks, hospitals, and other institutions having multiple computers connected via a network. Simple network management protocol (SNMP) is one solution for remotely managing devices connected via a network. SNMP can be used to monitor managed devices using a polling method or a trapping method. A polling method allows a network management system (NMS) to collect information from remotely managed devices by prompting the managed devices to send management messages to the NMS on a specific schedule. On the other hand, a trapping method allows remotely managed devices to automatically send management messages to an NMS without prompting. In a management message sent via SNMP, the source Internet protocol (IP) address is recorded in the IP header of the message and in the payload of the message.
For networked devices to communicate with each other, every networked device has a unique IP address. For example, each device connected to the Internet is assigned a unique IP address having the following format ###.###.###.###. As such, each device can be identified when necessary. A range of available IP addresses are reserved for use by private networks and the same private IP addresses can be used in different private networks. Request for comment (RFC) 1918 indicates that the private addresses include the IP addresses from 10.0.0.0 to 10.255.255.255, the IP addresses from 172.16.0.0 to 172.31.255.255, and the IP addresses from 192.168.0.0 to 192.168.255.255.
In certain instances, one private network may have a plurality of devices that have the same private IP address as devices in another private network. This typically is not a problem because the networks are private and are not interconnected. If the privately networked devices do interact via a public network, e.g., the Internet, network address translation (NAT) can modify the IP address in the header of a message in order to assign a unique identifier to the header of the message. However, NAT does not modify the payload of the message. When managing multiple private networks via a public network, it is possible for duplicate IP addresses to occur in the payloads of management messages. Thus, it can be very difficult to manage multiple private networks via a public network using SNMP and NAT.
Accordingly, there is a need for an improved system and method for managing multiple private networks via a public network.